Description: The Oligonucleotide Synthesis and Fermentor Shared Resource consists of two distinct components: an Oligonucleotide Synthesis Facility and a Fermentor Facility. The facility has been operational for over 10 years. The original facility, which had a single synthesizer, has now been expanded to include three different machines, capable of synthesizing a total of eight oligonucleotides at a time. Most of the support of this facility is derived from recharges to research grants. The current recharge rates are competitive with those of commercial companies for small scale synthesis of short oligonucleotides, and significantly cheaper for large scale synthesis of longer oligonucleotides and specially modified bases. In general, the application stated that it was possible to receive oligonucleotides on the same day of order, and in general the turn around time was one to two days for custom syntheses. Of note in the usage of the facility is that after a decline in usage in 1993-94 and 1994-95, usage increase in 1995-96. The facility will gel purify oligonucleotides at no additional charge upon request. Seventeen different investigators requested synthesis of oligonucleotides with modified bases. The fermentation facility maintains and operates two fermentors, one of 12 liter pilot scale and a second of 170 liter large scale capacity. The purpose of the facility is to offer large quantities of microbial cells for enzyme purifications and recombinant proteins for physical studies. The chargeback to investigators using the facility was significantly less than that cited for commercial sources. Usage of the facility included 26 charges to Center members, and 43 to non-members.